Many image capturing modules, for example, cameras, surveillance cameras, and the like, have a trend of becoming more compact and miniaturized. A conventional image capturing module usually includes a lens module for obtaining an optical image and a circuit board coupled to the lens module. The circuit board includes a plurality of functional modules for implementing different functions, such as a photoelectric converting module, an image processing module, an image transmitting module, a power supply module, a control module, and the like. The functional modules usually generate heat during operation. Since a volume of the image capturing module is limited, the functional modules need to be integrated within a small and closed space of the image capturing module. Therefore, the heat generated by the functional modules is difficult to be dissipated effectively and timely. If the heat is accumulated to a certain extent, the performance of the functional modules will be impacted, and the overall performance of the image capturing module will be impacted. A damage to the image capturing module can also occur in severe cases.